Threaded bolt and mounting therefor

ABSTRACT

A two-part threaded fastener comprising a bolt and a retainer captive on the bolt suitable for use as a vehicle headlamp reflector bowl adjustment screw. The bolt has a threaded shank which is formed with resilient projecting means adjacent to but spaced from an externally non-circular head. The retainer comprises a base having an aperture through which the resilient projecting means on the shank of the bolt is a force fit so that the base is captive between the head and the resilient means. The retainer is also formed with at least one upstanding wall and the head of the bolt with at least one face adapted to inter-engage with the wall on the retainer to resist relative rotation between the bolt and the retainer, the wall of the retainer being sufficiently resilient to allow rotation of the head of the bolt relative to the retainer when the bolt is subjected to a predetermined torque sufficient to deflect the wall.

United States Patent 1191 Seckerson 1 Jan. 1, 1974 1 THREADED BOLT ANDMOUNTING 143,524 /1921 Great Britain 151/52 THEREFOR 750,894 6/1956Great Britain 85/9 R [75] lnventor: Clifford Alexander Seckerson, lverHeath, Buckinghamshire, England [73] Assignee: TRW Inc., Cleveland, Ohio[22] Filed: Sept. 29, 1971 [21] Appl. No.: 184,754

[] Foreign Application Priority Data Oct. 5, 1970 Great Britain 47,319/

[52] [1.8. CI 151/49, 151/41.75, 151/69 [51] Int. Cl. Fl6b 39/26 [58]Field of Search 151/50, 52, 69, 49, l51/4l.75; 85/81, 9,

[56] References Cited UNITED STATES PATENTS 292,507 1/1884 Plummer151/50 1,427,953 9/1922 Harrison 151/69 2,244,570 6/1941 Pignam l5 l/SO2,560,961 7/1951 Knohl 151/69 2,899,733 8/1959 Sundberg 151/50 3,492,9103/1970 Van Niel et al. /81 3,561,516 2/1971 Reddy 151/69 FOREIGN PATENTSOR APPLICATIONS 397,710 France 151/52 Primary ExaminerEdward C. AllenAtt0rneyPhi1ip E. Parker et al.

[57] ABSTRACT A two-part threaded fastener comprising a bolt and aretainer captive on the bolt suitable for use as a vehicle headlampreflector bowl adjustment screw. The bolt has a threaded shank which isformed with resilient projecting means adjacent to but spaced from anexternally non-circular head. The retainer comprises a base having anaperture through which the resilient projecting means on the shank ofthe bolt is a force fit so that the base is captive between the head andthe resilient means. The retainer is also formed with at least oneupstanding wall and the head of the bolt with at least one face adaptedto inter-engage with the wall on the retainer to resist relativerotation between the bolt and the retainer, the wall of the retainerbeing sufficiently resilient to allow rotation of the head of the boltrelative to the retainer when the bolt is subjected to a predeterminedtorque sufficient to deflect the wall.

5 Claims, 8 Drawing Figures THREADED BOLT AND MOUNTING THEREFORBACKGROUND TO THE INVENTION The present invention relates to a threadedfastener comprising a bolt and a retainer captive on the bolt and alsoto an assembly including the fastener. The fastener of the presentinvention is particularly suitable for use as a vehicle headlampreflector bowl adjustment screw.

I have found that there is a need, in particular in the vehicle industryfor a threaded bolt which can be readily attached to a support panel insuch a manner that it is normally held against rotation relative to thesupport panel but which when subjected to a predetermined torque willrotate through a predetermined angle. This type of adjustable nut isparticularly useful in securing a vehicle headlamp reflector bowl inposition so that rotation of the nut causes axial displacement of thenut and tilting of the reflector bowl.

It is already known to provide a bolt which has a head and a cylindricalneck portion beneath the head which is captive in a circular aperture ina support panel. However, this known bolt has the disadvantage that itis freely rotatable relative to the support panel and can be used onlyin combination with a complex and expensive nut.

In contrast with the prior art, the present invention provides athreaded fastener comprising a bolt and retainer captive on the boltwhich is cheap to massproduce, easy to assemble and use and whichfurthermore ensures that the bolt can only be rotated relative to thesupport panel when subjected to a predetermined torque.

STATEMENT OF THE INVENTION A two-part threaded fastener comprising abolt which has a threaded shank and an externally non-circular head anda retainer which is captive on the bolt and which is adapted to resistrelative rotation between the bolt and the retainer, the shank beingformed with resilient projecting means adjacent to but spaced from thehead and the retainer comprising a base having an aperture through whichthe resilient projecting means is a force fit and being captive betweenthe head and the said resilient means, wherein the retainer is formedwith at least one upstanding wall and the head of the bolt is formedwith at least one face, the said wall and the said face being adapted tointer-engage to resist rotation of the bolt relative to the retainer andthe said wall being sufficiently resilient to allow rotation of the headof the bolt when the bolt is subjected to a predetermined torquesufficient to deflect the said wall.

DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are respectively a frontelevation and side elevation of a threaded bolt,

FIG. 3 is a section taken on the line Ill-Ill of FIG.

FIGS. 4, 5 and 6 are respectively a side elevation, end elevation andplan view of a retainer for use with the bolt of FIGS. 1 to 3,

FIG. 7 is an elevation showing the bolt of FIGS. 1 to 3 mounted in anapertured panel with the aid of the retainer of FIGS. 4 to 6 and,

FIG. 8 is a plan view of a part of the assembly shown in FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIGS. 1 to 3, a threaded boltis indicated generally at 10, which forms one part of a two partfastener of the present invention. The bolt 10 is formed from a suitablesynthetic plastics material such as an acetal resin by any convenientmethod such as by injection moulding.

The bolt 10 has a threaded shank 11, with a head 12 at one end and a tip13 at the other end which is substantially flat and non-circular insection. The head 12 is in the shape of a hexagonal-sided nut and isalso provided with an axially extending cruciform slot 14 in its outerface'for the reception of a screwdriver. Torque can thus be applied tothe head 12 by either a conventional spanner or by a screwdriver. Thebolt 10 can also be rotated by using pliers or a similar tool to gripthe tip 13 of the shank 11.

Immediately beneath the head 12 are a pair of resilient lugslS and 16which are inclined outwardly from the axis of the shank l1 and which aredirected towards the undersurface of the head 12.

FIGS. 4 to 6 illustrate a bolt retainer, which forms the other part ofthe two-part fastener of the invention and which is indicated generallyat 20. The retainer 20 comprises a flat base 21 having a circularaperture 22 and, extending upwardly from the base 21 in parallel and onopposite sides of the aperture 22, a pair of walls 23 and 24, whichserve to locate and restrain the head 12 of the bolt 10 when the bolt isassembled with the retainer. The walls 23 and 24 are formed with slots25 and 26 respectively, adjacent the base 21, which slots increase theresilience and flexibility of the walls 23 and 24.

The retainer 20 is preferably injection moulded from a syntheticplastics material, such as an acetal resin.

The bolt 10 and the retainer 20 are used to attach a vehicle headlampreflector bowl 30 to a support panel 31, in the manner shown in FIGS. 7and 8, so that the reflector bowl is positionally adjustable relative tothe panel.

The reflector bowl 30 has an integral annular surrounding flange 32which is formed with a circular aperture 33 to receive the bolt 10 andwith an upstanding wall portion 34 adjacent the aperture 33. The wallportion 34 is spaced from the centre of the aperture 33 by a distancewhich is equal to the distance a shown in FIG. 6 from the centre of theaperture 22 in the retainer 20 to a side of the retainer.

The support panel 31 is formed with an aperture 35 in which a threadednut 36 is mounted so as to be nonrotatable relative to the panel.

The retainer 20 is first mounted on the bolt 10 by passing the shank 11of the bolt through the circular aperture 22 in the retainer until thehead 12 of the bolt is seated between the upstanding walls 23 and 24 ofthe retainer. The diameter of the aperture 22 is such that the shank 11will pass through the aperture but the lugs 15 and 16 are compressed andthen sprung outwardly behind the retainer so that the retainer isthereafter captive on the bolt.

The free ends of the lugs 15 and 16 are spaced from the head 12 of thebolt by an amount greater than the depth of the base 21 of the retainer.As can be seen best from FIG. 8 the head 12 of the bolt fits snuglybetween the walls 23 and 24 of the retainer and is held against rotationby engagement of the walls against the opposite parallel sides of thehexagonal head 12. The walls are sufficiently flexible however to flexoutwardly when sufficient torque is applied to the head 12 of bolt toallow the bolt to rotate and snap into any one of six angular positionsrelative to the retainer.

When the bolt and retainer are assembled together as a unit the shank 11of the bolt is passed through the circular aperture 33 in the reflectorbowl flange 32, until the lugs 15, 16 pass through the aperture and snapoutwardly behind the flange to secure the bolt and retainer on theflange. As can be seen best from FIG. 8, a side of the base 21 of theretainer lies adjacent the wall portion 34 so that the retainer isnon-rotatable relative to the flange 32. The headlamp reflector bowlassembly is then brought up to the support panel 31 and the shank 11 ofthe bolt 10 is threaded into the nut 36 to secure the bowl assembly tothe support panel.

It will be appreciated that rotation of the bolt 10 will adjust theposition of the bowl relative to the support panel 31. This positionaladjustment can be achieved by applying torque with a screwdriver orspanner to the head of the bolt or by gripping and turning the tip 13 ofthe bolt shank. Rotation of the bolt 10 is achieved only by applyingsufficient torque to overcome the restraint of the walls 23 and 24 ofthe retainer 20 which thus provide step-wise rotation and indexing ofthe bolt.

lt will be understood that a bolt 10 and retainer 20 will be provided inat least two positions around the re-,

flector bowl 30 so that a tilting adjustment of the bowl relative to thesupport can be readily achieved.

The bolt 10 and retainer 20 are not limited to use in a reflector bowlassembly and can be used in any assembly where it is necessary toprovide stepwise rotation of a bolt relative to a member through whichthe bolt passes only when a predetermined torque is applied to the bolt.

The external shape of the head of the bolt can be modified to provideany even number of flat faces, it can be oval in shape or any otherconvenient noncircular shape.

Further minor modifications can be made to the above describedembodiment without departing from the spirit and scope of the inventionwhich is best described in the following claims.

What I claim is:

1. An installation comprising, in combination, an apertured, relativelyrigid support member and a two-part fastener assembly mounted on saidmember, said fastener assembly including a bolt having a head disposedat one side of said support member and a threaded shank joined to thehead and projecting through the aperture in the support member andbeyond the opposite side of said member, said shank carrying integral,resilient, support member engaging, projecting means, said projectingmeans being joined to the said shank in the vicinity of said head, butbeing spaced from the head and engaging said opposite side of saidsupport member, and a bolt locking retainer captive on said bolt shankbetween said head and said projecting means, but normally subject tolimited axial play relative to said shank between said head and saidprojecting means, said retainer having an apertured'base through whichsaid shank extends and said base, in said installation, being tensionedagainst said one side of said support member by the cooperative actionof said bolt and head bearing on said base and said projecting meansresiliently engaging said opposite side of said support member anddrawing said head toward said one side of said member, and cooperatinglocking means on said bolt head and said retainer restraining said boltagainst unintentional rotation relative to said support member, butpermitting intentional incremental rotation of said bolt relative tosaid support member, said locking means including at least two,resilient upstanding side walls joined to the base of said retainer,said walls being spaced apart and being disposed in substantiallyparallel planes and being provided with a slot adjacent said base toprovide improved resiliency and deflectability in said walls, said bolthead being snugly fitted between said walls and said walls beingoutwardly deflectable away from each other responsive to deliberaterotation of said bolt head, whereby, under normal usage conditions, theposition of said support member relative to another member carrying anut engaging said bolt shank may be adjusted responsive to deliberateincremental rotation of said bolt head with respect to said retainer,but said bolt shank is effectively restrained from unintentionalrotation responsive to vibratory forces acting on said installation.

2. An installation according to claim 1 wherein said bolt head is formedwith at least one side face and said face is in engagement with at leastone of said walls of said retainer.

3. An installation according to claim 2 wherein said bolt head has apolygonal configuration as viewed in elevation and has an even number ofside faces.

4. An installation according to claim 1 wherein said projecting means onsaid bolt shank comprises a plurality of flexible tongues disposed at anacute angle relative to the longitudinal axis of said shank and havingfree ends engaging said opposite side of said support member, saidtongues being deflectable both radially and longitudinally relative tosaid bolt shank.

5. An installation according to claim 1 wherein said bolt shank has anend portion remote from said head which is of a noncircularconfiguration and is adapted to be engaged by a tool for transmittingtorque to said bolt.

1. An installation comprising, in combination, an apertured, relativelyrigid support member and a two-part fastener assembly mounted on saidmember, said fastener assembly including a bolt having a head disposedat one side of said support member and a threaded shank joined to thehead and projecting through the aperture in the support member andbeyond the opposite side of said member, said shank carrying integral,resilient, support member engaging, projecting means, said projectingmeans being joined to the said shank in the vicinity of said head, butbeing spaced from the head and engaging said opposite side of saidsupport member, and a bolt locking retainer captive on said bolt shankbetween said head and said projecting means, but normally subject tolimited axial play relative to said shank between said head and saidprojecting means, said retainer having an apertured base through whichsaid shank extends and said base, in said installation, being tensionedagainst said one side of said support member by the cooperative actionof said bolt and head bearing on said base and said projecting meansresiliently engaging said opposite side of said support member anddrawing said head toward said one side of said member, and cooperatinglocking means on said bolt head and said retainer restraining said boltagainst unintentional rotation relative to said support member, butpermitting intentional incremental rotation of said bolt relative tosaid support member, said locking means including at least two,resilient upstanding side walls joined to the base of said retainer,saiD walls being spaced apart and being disposed in substantiallyparallel planes and being provided with a slot adjacent said base toprovide improved resiliency and deflectability in said walls, said bolthead being snugly fitted between said walls and said walls beingoutwardly deflectable away from each other responsive to deliberaterotation of said bolt head, whereby, under normal usage conditions, theposition of said support member relative to another member carrying anut engaging said bolt shank may be adjusted responsive to deliberateincremental rotation of said bolt head with respect to said retainer,but said bolt shank is effectively restrained from unintentionalrotation responsive to vibratory forces acting on said installation. 2.An installation according to claim 1 wherein said bolt head is formedwith at least one side face and said face is in engagement with at leastone of said walls of said retainer.
 3. An installation according toclaim 2 wherein said bolt head has a polygonal configuration as viewedin elevation and has an even number of side faces.
 4. An installationaccording to claim 1 wherein said projecting means on said bolt shankcomprises a plurality of flexible tongues disposed at an acute anglerelative to the longitudinal axis of said shank and having free endsengaging said opposite side of said support member, said tongues beingdeflectable both radially and longitudinally relative to said boltshank.
 5. An installation according to claim 1 wherein said bolt shankhas an end portion remote from said head which is of a noncircularconfiguration and is adapted to be engaged by a tool for transmittingtorque to said bolt.